Baling apparatus

ABSTRACT

Baling apparatus ( 2 ) for preparing highly compressed bales of materials such as silage, wool, paper, cardboard, plastics materials and scrap metal, the baling apparatus including a compression chamber ( 5 ) which includes two opposed gates ( 6, 7 ) which can be moved towards or away from each other by moving means ( 15, 16, 17, 18 ), to compress material between the gates into a bale; the gates being moved by moving means ( 15, 16, 18 ) which are mounted alongside the compression chamber ( 5 ).

TECHNICAL FIELD

The present invention relates to apparatus for forming bales of a rangeof different materials, and in particular to baling apparatus capable ofmaking highly compressed bales.

The apparatus of the present invention is especially well suited tomaking highly compressed bales of fragmented materials such as silage,hay, straw, wool, rags, paper, cardboard, plastics materials includingplastics containers, fibrous waste materials, and scrap metal.

The density of a highly compressed bale varies, depending upon thematerial in the bale; for a bale of silage (50 percent to 60 percent drymatter) a bulk density of 900 kilograms per cubic metre is typical; forbaled scrap cardboard a typical density would be 500 kilograms per cubicmetre.

BACKGROUND ART

Highly compressed bales have a number of advantages:—they providecompact storage and thus save space; they have better cohesion and areless prone to damage in handling. In the case of bales of silage andsimilar fodder, because the dense bale structure is less permeable toair than a conventional bale structure, the contents of the bale areless prone to oxidisation and to drying out than in a conventional bale.

In the case of baled silage, the reduced air permeability provided by ahighly compressed bale structure is especially valuable because it isimportant that silage should be stored under anaerobic conditions,because silage is preserved by the action of anaerobic bacteria.

Highly compressed silage bales have the further advantage that, for agiven weight of silage, a highly compressed bale gives a much smallersurface area to be sealed. It will be appreciated that silage must bewell sealed from the air (ideally, completely sealed from the air) foroptimum anaerobic digestion and good storage characteristics. Thedensity of the bale depends upon the compaction pressure and thecompaction time. Obviously, it is advantageous in a majority ofsituations to produce the bales as rapidly as possible, and the timetaken to achieve a given bulk density can be reduced by using anincreased compaction pressure. However, many materials have someelasticity, and therefore have hysteresis losses when compacted; toreduce such losses, it is necessary to use a lower compaction pressurefor a longer time.

It follows that, to optimise the efficiency of the compaction process,it is necessary to be able to adjust compaction pressures and compactiontimes to obtain rapid compaction but minimize hysteresis losses; thesefactors will vary according to the materials being compressed.

A further factor which must be taken into account is the size of thecompaction equipment:—while size seldom is critical for stationaryequipment, it is important that mobile equipment is not too large, sinceoverlong equipment is very difficult to move safely.

DISCLOSURE OF INVENTION

It is therefore an object of the present invention to provide apparatusfor forming highly compressed bales which allows the factors ofcompaction time and compaction pressures to be adjusted for maximumcompression in minimum time, but with minimum hysteresis losses.

Another object of the present invention is the provision of apparatuswhich is capable of compressing a load in two opposite directionssimultaneously, and hence increasing both the speed and efficiency ofcompression, but with the means for providing the compression soarranged that the overall length of the apparatus is kept to a minimum.

A further object of the invention is to provide a relatively inexpensivebaling apparatus which also is simple to use.

The present invention provides a baling apparatus comprising acompression chamber two dimensions of which are fixed and the thirddimension of which can be varied by the movement of two opposed gates,which can be moved towards or away from each other by the operation ofmoving means; said moving means being mounted alongside the compressionchamber parallel to said third dimension of said compression chamber.

Preferably the two fixed dimensions are the height and width of thecompression chamber and the third dimension is the length of thecompression chamber, with the opposed gates mounted one at each end ofthe compression chamber; each gate is movable by means of a pair ofmoving means.

Preferably also, the compression chamber includes a reinforced portionand the moving means are mounted on the outside of the reinforcedportion.

Preferably, each gate lies in a substantially vertical plane.

BRIEF DESCRIPTION OF DRAWINGS

By way of example only, preferred embodiments of the present inventionare described in detail with reference to the accompanying drawings, inwhich:—

FIG. 1 is a general side view of a first embodiment of the presentinvention;

FIG. 2 is an end view (on an enlarged scale) of the apparatus of FIG. 1,taken in the direction of arrow II;

FIG. 3 is a side view of part of FIG. 1;

FIG. 4 is an isometric view of part of FIG. 1, partly broken away;

FIG. 5 is a plan view, with the top of the apparatus removed;

FIG. 6 is a general side view of a second embodiment of the presentinvention;

FIG. 7 is an end view of the embodiment of FIG. 6, on a larger scale;

FIG. 8 is an isometric view of part of FIG. 6, partly broken away; and

FIG. 9 is a plan view of the apparatus of FIG. 6, with the top of theapparatus removed.

BEST MODES FOR CARRYING OUT THE INVENTION

Referring to FIGS. 1–5 of the drawings, a baling apparatus 2 designedparticularly for baling silage or similar fodder is constructed as atrailer unit adapted to be towed by means of a drawbar (not shown)mounted at the front 3 of the apparatus. The apparatus 2 is mounted on apair of wheels 4. The apparatus includes a central bale-formingcompression chamber 5 which is fixed in height but which can be alteredin length by moving a pair of gates 6,7, towards or away from eachother.

The forward gate 6 is movable from a position adjacent the forward end 8to the fully-compressed position shown in FIG. 1. The rear gate 7 ismovable from a position adjacent the rear end 9 to the position ofFIG. 1. The gates 6,7, can be moved independently of each other, butusually are moved simultaneously, as hereinafter described.

The chamber 5 is formed in three sections:—outer sections 5 a and 5 band an inner section 5 c. All sections are of the same height.

The outer sections 5 a, 5 b are of unequal length: the rear-most section5 b is longer than 5 a, to allow space for a formed bale to be removedfrom the apparatus. The sides 10, 11, of the sections 5 a, 5 b, areformed by vertically-spaced horizontal slats 12 which also act as guidesfor the gates 6, 7, as hereinafter described.

The inner section 5 c has solid sides 13; the length of this innersection is defined by the inner-most positions of the gates 6, 7, and isthe length of the fully-compressed formed bale since the greateststresses in the apparatus are upon section 5 c, each side 13 of section5 c is reinforced by a housing 14 which is secured to the trailerchassis and which provides anchorage points for four moving means in theform of hydraulic cylinders 15, 16, 17, 18 which move gates 6, 7.

Referring especially to FIG. 2, the rear gate 7 is controlled by theupper pair of hydraulic cylinders, 15 and 16.

The gate 7 is guided along the length of its travel by a spaced pair ofwheels 19, 20 mounted on the underside of the gate 7 and each engagedwith a guide channel 21, 22 which extend from the rear 9 of theapparatus to the front 8, along each side of the apparatus and alsoserve as guides for the wheels secured to the underside of the gate 6,only one of which, 23, is visible (FIG. 1).

The gate 7 is formed from a series of vertical slats 25 mounted in aframe, each outer end of which is formed as two pairs of box-sectionmembers 27–30 and 31–34 respectively. The innermost members 27, 30, 31,34 are arranged with their horizontal sides lying between or below theslats 12 forming the sides of compression chamber 5, so that the gate 7is free to slide in a horizontal plane.

The upper outermost members 28, 32 are welded by welds 35 to the rearends of connecting members in the form of I-cross-section channels 36,37 which extend along the interior of the members 28 and 32. Eachchannel 36, 37, extends to a position just forward of the housing 14.

Referring especially to FIGS. 2, 3 and 4, the hydraulic cylinders 15,16, are mounted within the channels 36,37 with the direction of strokeof each cylinder parallel to the longitudinal axes of the channels 36,37and the members 28,32.

Each cylinder 15,16, is mounted adjacent its inner end by a mountingbracket 40 secured to the housing 14, as shown in FIG. 3 with referenceto cylinder 15 only. The free end 41 of the associated rod 42 is rigidlysecured to a strong-point 43 (FIG. 4) adjacent the forward end of thechannel 36.

The cylinder 16 on the opposite side of the apparatus is mounted inexactly the same way as the cylinder 15. Thus, to move the gate 7forwards (i.e. in the direction of arrows A, FIGS. 1 and 4), fluid issupplied to the cylinders 15 and 16, extending the associated cylinderrods and moving the channels 36, 37, and hence the attached members27–32, and gate 7 all in the direction of arrow A. To reverse themovement of the gate 7, the cylinder rods are moved back into thecylinders 15, 16. A strip 43 a of low-friction material such as ‘Teflon’(Registered Trade Mark) is mounted beneath each channel 36, 37.

The front gate 6 is controlled by the two lower hydraulic cylinders17,18, in the same manner as the rear gate 7 is controlled by thecylinders 15 and 16, except that the cylinders 17 and 18 are mountedfacing in the opposite direction to cylinders 15 and 16. Thus, extensionof the cylinder rods associated with cylinders 17 and 18 moves thechannels secured thereto and the members attached to the channels, inthe direction of arrows B. FIGS. 3 and 4 show the cylinder 17 mounted inthe housing 14 by its mounting bracket 44, with the rod 45 of cylinder17 secured to channel 46.

Referring now to FIGS. 1 and 5 the floor and the roof of the compressionchamber 5 are partly formed by slatted conveyors 50,51, which aresupported upon spaced driven rollers in known manner and are arranged totravel in directions C and D respectively, to move material to becompacted (e.g. cut grass for silage) from the outer part of the chamber5 a towards the parts 5 c and 5 b. The forward end 52 of the roof can beleft open, or permanently closed. The forward end of the floor isoccupied by a pick-up feeder 53 which may be of any suitable know type(e.g. a ‘Strautmann’ feeder for a silage wagon) which is capable ofpicking up cut fodder from the ground and feeding it upwards intochamber 5 a, where the conveyors 50 and 51 move it towards the rear ofthe apparatus.

The roof of the section 5 b may be permanently closed or may be closedby removable flaps or hatches (not shown). The floor of section 5 b isclosed by a removable flap or latch (not shown).

Referring especially to the case of baling silage, the above—describedapparatus is used as follows:—first, grass is mowed and windrowed in theusual way. The apparatus 2 is connected to a suitable towing vehicle,and the gates 6,7 are moved (if necessary) respectively to the front andrear of the apparatus, giving a chamber 5 approximately 6 m long. Theapparatus 2 is then towed-along the windrows, with the pickup 53 driven,to pick up the cut grass and pass it upwards into the section 5 a, to bemoved rearwards by the conveyors 50 and 51. The pickup 53 may have areciprocating mower knife (not shown) mounted along its upper edge 54,to cut any long lengths of grass if necessary. This continues until thechamber 5 is packed with grass. The apparatus is then halted and thepickup 53 and knife are stopped. The rods of the hydraulic cylinders 15,16, 17, 18 are extended, to move the gates 6, 7, towards their inner(FIG. 1) positions one at each end of the section 5 c, which isapproximately 1.2 m long and about 0.7 m high. As the gates 6, 7, movetowards their inner positions, the conveyors 50,51; are driven sincethey help to move the grass towards the section 5 c. The degree ofcompression of the grass obviously depends upon how tightly-packed thegrass in the whole of the chamber 5 was before the gates 6, 7, weremoved inwards. However, the aim is to achieve a very highly compressedbale, with a bulk density of the order of 1000 kg/cubic metre and with adry matter content of at least 35%.

When the bale is fully compressed, it is tied or banded using anysuitable equipment (not shown), and the completed bale is dropped outthrough a lower trapdoor (not shown), in section 5 b. The gates 6 and 7then are moved back to their starting positions, and the whole procedureis repeated for the next bale.

The completed bales may be stored in any suitable manner.

It will be appreciated that the above-described apparatus may be variedin a number of ways, to suit different applications. For example, theapparatus may be used as a stationary baler, with feed from a top hoppere.g. through the roof. The size and shape of the baler may be varied tosuit particular applications. It also would be possible to rotate theapparatus through 90°, i.e. to feed material to be compressed in at oneside, with the gates 6 and 7 at the top and bottom of the compressionchamber.

The fact that the distribution within the compression chamber ofmaterial to be compressed can be accurately controlled by the speed andduration of use of the conveyors 50,51 means that an optimumdistribution can be achieved prior to compression, so that theefficiency of the compression also is optimised.

Further, the method of controlling the compression byhydraulically—controlled movement of the gates 6 and 7 permits veryaccurate control of the rate of movement of the gates, and hence allowsthe factors of compression time and pressure to be adjusted to achievemaximum compression in minimum time, with minimum hysteresis losses. Itwill be appreciated that the overall length of the apparatus is kept toa minimum by the fact that the hydraulic cylinders 15/17 and 16/18 aremounted one above the other, along the sides of the apparatus, ratherthan being mounted at the ends of the apparatus. Thus, the length of thecompression chamber 5 is kept as large as possible but the overalllength of the apparatus is minimized.

For baling materials such as card, waste plastics, paper or metal, asecond-embodiment of the apparatus as shown in FIGS. 6–9 is used. Inthis apparatus, the pickup 53 and associated apparatus is dispensedwith, and material to be bailed is loaded directly into the apparatus(e.g. by front-end loader) through the roof.

Referring to FIGS. 6–9, baling apparatus 59 is depicted as a trailerunit mounted on wheels 61 but may of course be constructed as astationary unit. The apparatus 59 includes a central bale formingcompression chamber 60 which extends for a major portion of the fulllength of the apparatus and which is fixed in height but can be alteredin length by moving an opposed pair of gates 63,64, best seen in FIG. 9,towards or away from each other.

The forward gate 63 can be moved from a position adjacent the front end65 of the apparatus to the fully compressed position shown in FIG. 9.The rear gate 64 can be moved from a position at the rear end 62 of theapparatus, to the fully compressed position shown in FIG. 9. The gates63,64 can be moved independently or simultaneously.

Most of the sided of the compression chamber 60 are formed by verticallyspaced horizontal slats 66 which also act as guides for the gates 63,64as hereinafter described. However, over the portion 60 a of thecompression chamber where the final bale compression takes place, thesides of the chamber are solid, for additional strength.

The rear portion 67 of the top of the apparatus is permanently closed bya solid roof plate. The forward portion of the top of the apparatus canbe opened for loading purposes, and is closed by two top doors 68,69,which are pivotally mounted on pivots 70,71 and are opened and closed byhydraulic cylinders 72,73. Each top door 68,69 can be moved by itscorresponding control cylinders 72,73 between the fully closed positionshown in FIG. 6 and a loading position in which each door 68,69 ispivoted upwards, clear of the opening, allowing free access into the topof the apparatus for loading in materials to be compressed. Thematerials can be loaded by any suitable means e.g. bucket, conveyor oreven manually.

The bottom of the apparatus is permanently closed except for a hatch(not visible) located at the base of the portion 60 a, to allow forremoval of the formed bale. The hatch is hinged along one longer edgeand is opened and held closed by a hydraulic cylinder, (not shown).

Each gate 63,64 is controlled by moving means in the form of a pair ofhydraulic cylinders 74,75/76,77 respectively. The cylinders are mountedalong the sides of the apparatus, with one cylinder of each pair on oneside of the apparatus, and the other cylinder of each pair on theopposite side of the apparatus. The cylinders 74,75 for the rear gate 64are mounted vertically above the cylinders 76,77 for the front gate 63.

Each of the cylinders 74–77 is anchored to a reinforced bulkhead portion78 which surrounds and reinforces the bale forming portion 60 a, andwhich is secured to the chassis of the apparatus. The end of each of thecylinders from which the cylinder rod protrudes is rigidly mounted tothe bulkhead 78, with the length of each cylinder extending parallel tothe length of the apparatus. The cylinder rod of each cylinder isrigidly secured to a connecting member in the form of a channel member80,81,82, 83 adjacent one end of the member. The base of each channelmember extends beneath and parallel to the corresponding cylinder, withthe sides of the channel member one on each side of the cylinder. Theupper channel members 80,82 extend from the rear to just beyond thebulkhead 78. The lower channel members 81,83 extend from the front tojust beyond the bulkhead 78.

The cylinders 74,75 for the rear gate 64 are mounted with the closedends of the cylinders closest to the rear gate i.e. so that when thecylinder rods 74 a,75 a, of the cylinders are extended, they travel awayfrom the rear gate. The cylinders 76,77 for the front gate 63 aremounted the opposite way around to the cylinders 74,75, so that when thecylinder rods of the cylinders 76,77 are extended, they travel away fromthe front gate.

The end side portions of the upper and lower channel members80,82,/81,83 are rigidly secured (e.g. by welding) to the rear gate64/front gate 63 respectively. Each gate 63, 64 consists of arectangular frame 90 supporting a series of vertical struts 91 and twopairs of box section members 92, 93, 94, 95, one pair at each end of theframe. FIG. 7 shows the rear gate 64; the front gate is arranged in thesame manner, as partially shown in FIG. 8, which shows the upper andlower box sections 92 a,93 a which form part of the front gate. As shownin FIG. 7, the horizontal members of the frame 90 pass between thehorizontal slats 66 forming the sides of the apparatus, so that theslats act as a guide for the movement of the gate. The box sections92–95 accommodate the channel members 80–83, which can slide relative tothe box sections on pads 96 of low friction plastics material.

The lower surface of each gate 63,64 is provided with a sliding surfaceof low friction plastics material, (not shown).

To move the rear gate 64, hydraulic fluid is supplied to the cylinders74,75 to extend the cylinder rods. As the cylinder rods extend, theymove in the direction of Arrow A (FIG. 8) and pull the associatedchannel members 80,82 in the same direction, drawing the rear gate 64forward in a direction of Arrow A. To move the gate 64 in the oppositedirection, the cylinder rods are retracted, moving the channel members80,82 and the gate 64 back towards the rear of the apparatus.

The forward gate 63 is moved in a similar manner:—when hydraulic fluidis supplied to the cylinders 76,77 and the associated cylinder rodsextended, the cylinder rods and the channel members 81,83 are moved inthe direction of Arrow B, drawing the forward gate in the samedirection. The forward gate is moved in the opposite direction byretracting the cylinder rods, thus moving the channel members 81,83 andthe gate 63 towards the front of the apparatus.

The above described apparatus is used as follows: the apparatus is towedto the desired position and is made secure. The top doors 68,69 arepivoted to the fully open position using the hydraulic cylinders 72,73,and the end gates 63,64 are moved to their fully apart position i.e.with the rear end gate 64 adjacent the end of the apparatus and thefront gate 63 adjacent the front of the apparatus.

A first load of material to be baled (e.g. scrap cardboard) is loadedinto the compression chamber 60 through the open top doors 68,69 using abucket loader. The top doors 68,69 are closed, and the material in thecompression chamber is moved in the direction of arrow L (FIG. 9) bymoving the forward gate 63 towards the rear of the apparatus.

The forward gate 63 is then returned to its initial position, the topdoors 68,69 are opened again and a further load is loaded into thecompression chamber 60 and is moved forward by the forward gate 63. Thesequence is repeated until either a specified weight has been loadedinto the compression chamber 60 and/or the hydraulic pressure requiredto move the forward gate 63 reaches a specified value. When this stageis reached, both forward and rear gates 63,64 are moved towards eachother for a final compression of the load. In the final compressionstage, the forward gate 63 is moved in the direction of arrow L untilthe gate reaches the position shown in FIG. 9, adjacent the forward edgeof the bulkhead 78, just behind the rear top door 69; this reduces thelevel of pressure applied to the top doors. The rear gate 64 is thenmoved in the direction of arrow R until the hydraulic pressure in thehydraulic cylinders moving the front and rear gates is equal. A finalcompression is then applied by both forward and rear gatessimultaneously.

The final compression takes place in the chamber 60 a which isreinforced by the bulkhead 78 and is clear of the top doors. Localisingin the final compression in this way means that it is necessary toreinforce only a relatively small area of the apparatus.

The formed bale is then tied off using any suitable automatic tyingsystem. The tied bale is extracted from the chamber 60 a by opening ahatch in the floor of the chamber 60 a, withdrawing the rear gate 64 andthen allowing the bale to fall out under gravity or, if necessary,pushing the bale away from the forward gate 63 by using an extractionhydraulic cylinder 98 which moves a pusher plate 99 (shown in FIG. 9only, in the extended position) outwards from the inner wall of the gate63, to push the bale away from the gate 63 and allow the bale to fall.

The apparatus is then returned to the start position, and the sequencerepeated. It will be appreciated that the apparatus may be scaled up orscaled down as required. The hydraulic cylinders 74–77 could be replacedby pneumatic cylinders or by linear electric motors (depending upon therequired pressure).

Further, the hydraulic cylinders or alternative moving means could beconnected directly to the gates 63,64, i.e. the cylinder rods could beconnected directly to the respective gates rather than being connectedto the gates via the channel members. However, this arrangement has thedrawback that when the gates are moved to the fully apart position, thecylinder rods are extended; since the apparatus normally would be inthis position during transport, there would be a greater risk of damageto the cylinder rods.

1. A baling apparatus comprising a compression chamber having a fixedheight and width but a variable length, said length being defined byfirst and second opposed gates which are located one at each end of thecompression chamber, each said gate being movable towards or away fromthe other gate by a pair of moving means, one moving means of each pairof said two pairs of moving means being mounted alongside the length ofthe compression chamber on one side of the chamber, and the other movingmeans of each pair of said two pairs of moving means being mountedalongside the length of the compression chamber on the opposite side ofthe compression chamber; the pair of moving means associated with thefirst gate lying in a first horizontal plane and the pair of movingmeans associated with the second gate lying in a second horizontalplane; said first horizontal plane being vertically above said secondhorizontal plane.
 2. The baling apparatus as claimed in claim 1, whereinthe compression chamber includes a reinforced portion, having wallswhich are reinforced to take a higher pressure than a part of thechamber not included in said reinforced portion; said moving means beingmounted upon the outside of said reinforced portion.
 3. The balingapparatus as claimed in claim 2, wherein each moving means includes afirst member capable of linear displacement relative to a second memberwhen said moving means is activated; the second member of each movingmeans being secured to said reinforced portion of the compressionchamber; the first member of each moving means being connected to one ofsaid gates, such that activation of one pair of moving means connectedto one of said gates causes linear movement of said one gate towards oraway from said reinforced portion, and activation of the other pair ofmoving means connected to the other of said gates causes linear movementof said other gate towards or away from said reinforced portion.
 4. Thebaling apparatus as claimed in claim 3, wherein the first member of eachmoving means is connected to the corresponding gate by a connectingmember secured between said gates and said first member; and whereineach moving means is oriented relative to the corresponding gate suchthat linear displacement of said first member of said moving means awayfrom said second member moves the corresponding gate towards saidreinforced portion.
 5. The baling apparatus as claimed in claim 2,wherein said compression chamber includes a first portion adjacent saidreinforced portion, said first portion being adapted to receive materialto be compressed.
 6. The baling apparatus as claimed in claim 5, whereinsaid first portion has a top which can be opened and closed.
 7. Thebaling apparatus as claimed in claim 6, wherein at least part of abottom of said compression chamber can be opened or closed, to permit abale to be removed therefrom.
 8. The baling apparatus as claimed inclaim 1, wherein the apparatus is mobile.
 9. The baling apparatus asclaimed in claim 8, wherein the apparatus is mounted upon a trailer. 10.The baling apparatus as claimed in claim 1, wherein each said gate ismovable by said corresponding pair of moving means independently of theother gate or simultaneously with the other gate.
 11. The balingapparatus as claimed in claim 3 or claim 4, wherein said moving meansare selected from the group consisting of: hydraulic cylinder, pneumaticcylinder, linear electric motor.
 12. The baling apparatus as claimed inclaim 5, further including a conveyor arranged to convey material to becompressed to said first portion.